1. Field of the Invention
The invention relates to a communication network in which information is routed through an array of interconnected nodes and more particularly to the identification of nodes in messaging in ad hoc networks.
2. Related Art
In a communication system in which communications among subscribers are routed through a network of interconnected routers or nodes to provide required communication paths, each node includes a database which stores information on the network configuration obtained from messages exchanged among the nodes. The network information stored in the database in each node provides a representation of the network configuration that is used by protocols controlling the node operation to direct data traffic through the network from a source node to a destination node.
An ad hoc communication network, for example, has both routing nodes capable of network routing functions and nodes that are endpoints, sources or destinations, for data traffic. All of the ad hoc network nodes are equipped with communication transceivers. Further, all nodes execute processes and protocols that enable the nodes to locate all of the other nodes, to determine the paths through the network for data traffic between designated sources and destinations, and to detect and repair disruptions in the network as communication paths characteristics vary over time and nodes move and fail for various reasons. The network configuration representation stored in the databases of the nodes is utilized to perform the processes and protocols executed at the network nodes.
A node identifier that is unique is assigned to identify a single router, switch or host in the network or to identify a communication interface in a router, switch or host. The information data in the messages exchanged among nodes performing the communication protocols is stored in units according to the node identifier of the nodes issuing the messages in the node database. During operation of the network, a routing protocol uses the unique node identifier to identify the node that issued a routing update or other routing information. A forwarding protocol may provide a list of nodes according to their unique node identifiers that should be traversed to deliver a packet across the network and a channel access protocol may embed the unique node identifier as part of its channel access arrangement.
In the event that the assigned node identifiers are not unique due to a configuration error, the same node identifier may be used for different nodes in the network. The sharing of unique node identifiers interferes with proper operation of the networking protocols. For example, the duplicated node identifiers will not permit Link State and Distance Vector routing protocols to accurately discern paths through the network so that data packets are misrouted. Additionally, channel access does not prevent contention or collisions when two nodes in a wireless network that are within wireless range of each other have the same assigned node identifier and each responds to a channel access request that includes the duplicated unique node identifier. Accordingly, it is necessary to assure detection and correction of duplicated node identifiers in communication networks to avoid failure in node operation.